Rolling element crown rings, especially those installed in bearings often manifest a large rolling element sag, i.e., the rolling elements fall downwards within the pocket due to the force of gravity so that a gap arises between their rolling contact surface and the outer raceway. This sag has the effect that a shaft which has to be introduced into the bearing abuts with its end face against the end faces of individual cylinder rollers thus causing problems in the introduction of the shaft into the bearing. Due to this, an automatic assembly is not possible.
According to the solution described in U.S. Pat. No. 3,051,534, this sag of the rolling elements is prevented by arranging a second ring above or below the actual cage, said ring comprising retaining sections which press the rolling elements guided in the cage against the inner or the outer raceway, as the case may be.
However, this type of rolling element retention is very complicated and thus also expensive because, besides the actual bearing cage, a further retaining element has to be manufactured and installed in the bearing. In addition, such a solution incorporates the danger that due to the close guidance between the rolling elements and the cage, or between the rolling elements and the additional ring, the operation of the bearing is impaired.